Galloway was played by David L. Ross. The redshirt character did not have a set identity until Kirk referred to him as "Lieutenant Galloway" in his fourth appearance in "A Taste of Armageddon".

The shooting script for The City on the Edge of Forever called him Davis.

Galloway was the second Star Trekrecurring character, after Leslie, to return from the dead without explanation. Captain Tracey killed him with a phaser blast in "The Omega Glory". Ross appeared in "Day of the Dove" in the role of Lieutenant Johnson. He appeared again in "Turnabout Intruder" with the onscreen credit spelled as "Lt. Galoway".

In Star Trek II: Short Stories, Galloway was born and raised on Mars. He attended Starfleet Security Forces School for training as a security guard. After graduation, he served aboard Federation starships USS Leo, USS Jassan, USS Nelson and USS Thelonii before joining the Enterprise. By 2277, he was the security chief on the Enterprise and held the rank of sergeant.